1: Obtain a Zoomed CFD of the AV in the mid Transgastric
or Deep Transgastric view. If there is a sufficiently
stenosed aortic valve, a PISA formation will occur.
The distance from the center of the PISA formation
to it's first aliasing velocity edge (where the color
shifts from blue to red) is the radius of the PISA
2: Note the aliasing velocity. The aliasing
velocity is the velocity where if the flow exceeds
this velocity the flow will be displayed with colors
from the opposite scale.
3: Obtain a continuous wave doppler (CWD) of the
aortic valve. The CWD of the aortic valve
will yield a flow profile where, utilizing the calipers
(or you can trace it) to show the peak velocity.
The peak velocity is the Vmax which is typically 5
Step 4: Obtain an
angle of the PISA formation: The angle at the aortic valve is
typically 180 degrees, whereas the angle at the mitral valve (for
mitral stenosis calculations) is typically 120 degrees.
Step 5: Determine the LVEF and enter the above data. The degree of aortic stenosis can then be calculated.
Normal Area 2.5-4.5 cm2
Mild Stenosis 1.0-2.5 cm2
Moderate Stenosis 0.75-1.0 cm2
Severe Stenosis < 0.75 cm2
This activity has been planned and implemented in accordance with the accreditation requirements and policies of the Accreditation Council for Continuing Medical Education through the joint providership of University of Nebraska Medical Center, Center for Continuing Education and JLS Interactive, LLC.
The University of Nebraska Medical Center, Center for Continuing Education is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.
This activity is approved by the American Society of Radiologic Technologists (ASRT) as sonography-related continuing education (CE). Credit(s) issued for successful completion of ASRT-approved CE activities are accepted by the American Registry of Diagnostic Medical Sonography, American Registry of Radiological Technologists, Cardiovascular Credentialing International and Canadian Association of Registered Diagnostic Ultrasound Professionals. Contact the applicable registry for additional information / restrictions on their acceptance of ASRT CE credit.